Barter is the present and the future of international trade, especially for people who is starting in the import export business. Barter and more: Triangular operations.
1. After adding water to the cup, tighten the cork and lid in a clockwise direction, and place the cup flat on the table. There should be no water leakage. See if the tightness is good.
2. Check whether the vacuum insulation of the cup is good. Pour boiling water into the thermos cup and tighten the cork or lid clockwise for 2-3 minutes. Touch the outer surface of the cup with your hands. If the cup is obviously warm , indicating that the product has lost the vacuum degree and cannot achieve a good thermal insulation effect.
3. Identify the quality of plastic parts: The characteristics of food-grade new plastics are small smell, bright surface, no burrs, long service life and not easy to age. Ordinary plastics or recycled plastics are characterized by strong odor, dark color, many burrs, and plastics are easy to age and break.
4. It is not that the heavier the cup, the better. The depth of the inner tank of the thermos cup is basically the same as the height of the outer shell, and the capacity (the difference is 16-18MM) is consistent with the nominal value. Some poor quality thermos cups add sand and cement blocks to the cup to make up for the missing weight.
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